How to use lambda operator in Python?

 To use the lambda operator in Python, you simply need to use the following syntax:

Python

lambda parameters: expression

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The parameters can be any number of arguments, and the expression is the expression that will be evaluated and returned when the lambda function is called.

Here is a simple example of a lambda function:

Python

add_two_numbers = lambda x, y: x + y

print(add_two_numbers(1, 2))

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Output:

3

Lambda functions can be used in a variety of ways, including:

• To pass anonymous functions to other functions:

Python

def apply_function(function, argument):
  return function(argument)

print(apply_function(lambda x: x * 2, 10))

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Output:

20

• To create simple functions on the fly:

Python

numbers = [1, 2, 3, 4, 5]

# Create a lambda function to double each number in the list
double_numbers = lambda x: x * 2

# Apply the lambda function to the list using the map() function
doubled_numbers = map(double_numbers, numbers)

# Print the doubled numbers
print(list(doubled_numbers))

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Output:

[2, 4, 6, 8, 10]

• To sort a list or other iterable using a custom key function:

Python

numbers = [1, 5, 3, 2, 4]

# Create a lambda function to sort the numbers in descending order
sort_by_descending_order = lambda x: -x

# Sort the list using the lambda function
numbers.sort(key=sort_by_descending_order)

# Print the sorted list
print(numbers)

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Output:

[5, 4, 3, 2, 1]

Lambda functions can be a very powerful tool in Python, and they can be used to make your code more concise and expressive.

Here are some additional tips for using lambda functions in Python:

• Use lambda functions for short, simple expressions. If the expression is complex or long, it is better to define a regular function.
• Use lambda functions to pass anonymous functions to other functions. This can make your code more concise and readable.
• Use lambda functions to create custom key functions for sorting lists and other iterables.

I hope this helps!